Add test for old compiler ICE when using `Borrow`
The original issue was caused by implementing `Borrow` on a local type and using the tokio-reactor crate which had this impl: https://github.com/tokio-rs/tokio/blob/tokio-0.1.4/tokio-reactor/src/poll_evented.rs#L547-L577
This causes an ICE on Rust 1.27.0:
```console
$ RUSTUP_TOOLCHAIN=1.27.0 rustc src/test/ui/issues/issue-50687-ice-on-borrow.rs
error: internal compiler error: librustc/traits/structural_impls.rs:180: impossible case reached
thread 'main' panicked at 'Box<Any>', librustc_errors/lib.rs:554:9
note: Run with `RUST_BACKTRACE=1` for a backtrace.
error: aborting due to previous error
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
note: rustc 1.27.0 (3eda71b00 2018-06-19) running on x86_64-apple-darwin
```
Closes#50687
Resolve UB in Arc/Weak interaction (2)
Use raw pointers to avoid making any assertions about the data field.
Follow up from #72479, see that PR for more detail on the motivation.
@RalfJung I was able to avoid a lot of the changes to `Weak`, by making a helper type (`WeakInner`) - because of auto-deref and because the fields have the same name, the rest of the code continues to compile.
Update books
## reference
7 commits in 892b928b565e35d25b6f9c47faee03b94bc41489..becdca9477c9eafa96a4eea5156fe7a2730d9dd2
2020-05-11 11:13:51 -0700 to 2020-05-21 21:08:02 +0100
- Update tuple index token. (rust-lang-nursery/reference#814)
- Fixes minor errors (rust-lang-nursery/reference#818)
- Update that macros can be deprecated. (rust-lang-nursery/reference#813)
- work on char/str descriptions (rust-lang-nursery/reference#809)
- cfg_attr needs a valid predicate (rust-lang-nursery/reference#812)
- Account for removal of UB in float-to-int casts (rust-lang-nursery/reference#810)
- Fix stray plus signs. (rust-lang-nursery/reference#811)
## book
6 commits in 6247be15a7f7509559f7981ee2209b9e0cc121df..e8a4714a9d8a6136a59b8e63544e149683876e36
2020-05-03 10:55:09 -0500 to 2020-05-25 10:29:27 -0500
- code is 1024 now, not 512
- Clean up install a bit
- We don't need build.sh anymore
- Fix CI status in README
- Port to github actions (rust-lang/book#2337)
- operating system -> allocator
## rust-by-example
5 commits in ab072b14393cbd9e8a1d1d75879bf51e27217bbb..7aa82129aa23e7e181efbeb8da03a2a897ef6afc
2020-05-09 08:46:39 -0300 to 2020-05-25 14:54:26 -0300
- Person of age 0 is alive (rust-lang/rust-by-example#1348)
- Gramatical fix in std/rc.md (rust-lang/rust-by-example#1347)
- Capture example should use String (rust-lang/rust-by-example#1331)
- Fix empty bound examples (rust-lang/rust-by-example#1343)
- Fix an inline comment in macros/repeat.md (rust-lang/rust-by-example#1344)
## edition-guide
1 commits in 49270740c7a4bff2763e6bc730b191d45b7d5167..0a8ab5046829733eb03df0738c4fafaa9b36b348
2020-05-11 08:50:29 -0500 to 2020-05-18 08:34:23 -0500
- Changes for Rust 1.32 & setup for edition-next (rust-lang-nursery/edition-guide#213)
## embedded-book
3 commits in 366c50a03bed928589771eba8a6f18e0c0c01d23..5555a97f04ad7974ac6fb8fb47c267c4274adf4a
2020-05-07 09:04:42 +0000 to 2020-05-25 18:00:51 +0000
- Remove reference to const-fn feature of cortex-m. Closesrust-embedded/book#242. (rust-embedded/book#243)
- Spelling: Appplication -> Application (rust-embedded/book#241)
- QEMU debugging updates (rust-embedded/book#239)
Warn about unused crate deps
Implements #57274 by adding -Wunused-crate-dependencies. This will warn about any `--extern` option on the command line which isn't referenced by the crate source either via `use` or `extern crate`.
Crates which are added for some side effect but are otherwise unreferenced - such as for symbols they define - the warning can be suppressed with `use somecrate as _;`.
If a crate has multiple aliases (eg using `foo = { package = "bar" }` in `Cargo.toml`), then it will warn about each unused alias.
This does not consider crate added by some other means than `--extern`, including the standard library. It also doesn't consider any crate without `add_prelude` set (though I'm not sure about this).
Unfortunately this probably [does not yet work well with Cargo](https://github.com/rust-lang/rust/issues/57274#issuecomment-624839355) as it will over-specify crates, causing spurious warnings. As a result, this lint is "allow" by default and must be explicitly enabled either via `#![warn(unused_crate_deps)]` or with `-Wunused-crate-deps`.
JS cleanup
The goal here is just to improve the source code a bit. I recommend to review one commit at a time, otherwise it might not make much sense. :)
The biggest commit is the second one: to prevent to have "global" variables declared in `main.js` (and thus prevent name conflict or overwriting), I moved such code into anonymous functions.
r? @kinnison
cc @rust-lang/rustdoc
add a lint against references to packed fields
Creating a reference to an insufficiently aligned packed field is UB and should be disallowed, both inside and outside of `unsafe` blocks. However, currently there is no stable alternative (https://github.com/rust-lang/rust/issues/64490) so all we do right now is have a future incompatibility warning when doing this outside `unsafe` (https://github.com/rust-lang/rust/issues/46043).
This adds an allow-by-default lint. @retep998 suggested this can help early adopters avoid issues. It also means we can then do a crater run where this is deny-by-default as suggested by @joshtriplett.
I guess the main thing to bikeshed is the lint name. I am not particularly happy with "packed_references" as it sounds like the packed field has reference type. I chose this because it is similar to "safe_packed_borrows". What about "reference_to_packed" or "unaligned_reference" or so?
Export ZERO_AR_DATE for macos linker invocations
This commit attempts to improve reproducibility of builds on macOS by
exporting the `ZERO_AR_DATE=1` environment variable for all invocations
of the linker. While it looks like this env var is targeted at just the
`ar` command (which does actually read this) it appears that recent-ish
versions of the linker *also* read this environment variable. This
env var forces the linker to set a deterministic zero value for the
mtime in the N_OSO field of the object file.
Currently it's believe that older versions of the linker will simply
ignore this env var, while newer versions will read it and produce a
deterministic output for compilations with debuginfo.
Closes#47086Closes#66568
This commit attempts to improve reproducibility of builds on macOS by
exporting the `ZERO_AR_DATE=1` environment variable for all invocations
of the linker. While it looks like this env var is targeted at just the
`ar` command (which does actually read this) it appears that recent-ish
versions of the linker *also* read this environment variable. This
env var forces the linker to set a deterministic zero value for the
mtime in the N_OSO field of the object file.
Currently it's believe that older versions of the linker will simply
ignore this env var, while newer versions will read it and produce a
deterministic output for compilations with debuginfo.
Closes#47086Closes#66568
This will print a diagnostic for crates which are mentioned as `--extern`
arguments on the command line, but are never referenced from the source.
This diagnostic is controlled by `-Wunused-crate-dependencies` or
`#![warn(unused_crate_dependencies)]` and is "allow" by default.
There are cases where certain crates need to be linked in but are not
directly referenced - for example if they are providing symbols for C
linkage. In this case the warning can be suppressed with
`use needed_crate as _;`.
Thanks to @petrochenkov for simplified core.
Resolves issue #57274
Fix bug in shebang handling
Shebang handling was too agressive in stripping out the first line in cases where it is actually _not_ a shebang, but instead, valid rust (#70528). This is a second attempt at resolving this issue (the first attempt was reverted, for, among other reasons, causing an ICE in certain cases (#71372, #71471).
The behavior is now codified by a number of UI tests, but simply:
For the first line to be a shebang, the following must all be true:
1. The line must start with `#!`
2. The line must contain a non-whitespace character after `#!`
3. The next character in the file, ignoring comments & whitespace must not be `[`
I believe this is a strict superset of what we used to allow, so perhaps a crater run is unnecessary, but probably not a terrible idea.
Fixes#70528
Perform MIR NRVO even if types don't match
This is the most straightforward way to resolve#72428, but it could cause problems in codegen since the type of `_0` may no longer match the return type of the body.
add regression tests for stalled_on const vars
closes#70180
Afaict this has been fixed sometime after #70213
`trait_ref_type_vars` correctly adds const infers and I did not find any remaining `FIXME`s which correspond to this issue.
7c59a81a5f/src/librustc_trait_selection/traits/fulfill.rs (L555-L557)
Added both examples from the issue as regression tests and renamed `trait_ref_type_vars` -> `trait_ref_infer_vars`.
r? @eddyb
Rollup of 4 pull requests
Successful merges:
- #72153 (exhaustively check `ty::Kind` during structural match checking)
- #72308 (Emit a better diagnostic when function actually has a 'self' parameter)
- #72560 (Enable `glacier` command via triagebot)
- #72567 (Clean up E0608 explanation)
Failed merges:
r? @ghost
Emit a better diagnostic when function actually has a 'self' parameter
Fixes#66898
When we are unable to resolve a reference to `self`, we current assume
that the containing function doesn't have a `self` parameter, and
emit an error message accordingly.
However, if the reference to `self` was created by a macro invocation,
then resolution will correctly fail, due to hygiene. In this case, we
don't want to tell the user that the containing fuction doesn't have a
'self' paramter if it actually has one.
This PR checks for the precense of a 'self' parameter, and adjusts the
error message we emit accordingly.
TODO: The exact error message we emit could probably be improved. Should
we explicitly mention hygiene?
exhaustively check `ty::Kind` during structural match checking
This was prone to errors as we may forget new kinds in the future.
I am also not yet sure about some kinds.
`ty::GeneratorWitness(..) | ty::Infer(_) | ty::Placeholder(_) | ty::UnnormalizedProjection(..) | ty::Bound(..)` might be unreachable here.
We may want to forbid `ty::Projection`, similar to `ty::Param`.
`ty::Opaque` seems fine afaict, should not be possible in a match atm.
I believe `ty::Foreign` should not be structurally match, as I don't even know what
that would actually mean.
r? @pnkfelix cc @eddyb
Shebang handling was too agressive in stripping out the first line in cases where it is actually _not_ a shebang, but instead, valid rust (#70528). This is a second attempt at resolving this issue (the first attempt was flawed, for, among other reasons, causing an ICE in certain cases (#71372, #71471).
The behavior is now codified by a number of UI tests, but simply:
For the first line to be a shebang, the following must all be true:
1. The line must start with `#!`
2. The line must contain a non whitespace character after `#!`
3. The next character in the file, ignoring comments & whitespace must not be `[`
I believe this is a strict superset of what we used to allow, so perhaps a crater run is unnecessary, but probably not a terrible idea.
First draft documenting Debug stability.
Debug implementations of std types aren't stable, and neither are derived Debug implementations for any types, including user-defined types. This commit adds a section to the Debug documentation noting this stability status.
This issue is tracked by #62794.
librustc_middle: Rename upvars query to upvars_mentioned
As part of supporting RFC 2229, we will be capturing all the Places that
were mentioned in the closure.
This commit modifies the name of the upvars query to upvars_mentioned.
r? @nikomatsakis @blitzerr @matthewjasper
